IUE factsheet

Ultraviolet spectroscopic observations of cosmic objects, from comets to quasars

Name IUE stands for the International Ultraviolet Explorer.

Description The IUE is the longest-lived and one of the most productive satellites ever built. It worked non-stop (only one week of programme interruption was made in 1985) until it was switched off in September 1996, 14 years later than originally planned. Although IUE produced no images, it provided invaluable data by measuring the energies of ultraviolet rays coming from celestial objects, giving insight into the physical conditions in those objects.

Launch 26 January 1978 (Delta 2914 at Cape Canaveral, United States).

Status Completed (1996).

Journey IUE was placed into a geosynchronous orbit above the Atlantic Ocean.

Notes IUE was the first general-user space observatory.

IUE was the first astronomical satellite in high Earth orbit.

IUE detected the ultraviolet radiation that cannot penetrate the Ozone layer and therefore will not reach telescopes on the ground. Everything from far-off supernovae to approaching comets came under IUE' s analytical gaze.

Key observations included Halley's Comet during its 1986 visit, the first space observations of a naked eye visible supernova event in 300 years in the nearby galaxy LMC in 1987, and the extensive observational program detailing the evolution of the Jupiter atmosphere after the impact of Comet Shoemaker-Levy in 1994. Astronomers continue to work with the wealth of data now stored in the IUE final archive.

While IUE gave up any claims to be state-of-the-art long ago, the reliability of its operation throughout its lifetime was staggering. The primary cameras all remained fully operational.